Mechanically reinforced, transparent, anti-biofouling thermoplastic resin composition and manufacturing method thereof

ABSTRACT

This invention discloses a transparent standalone resin or masterbatch concentrate composition and manufacturing method of transforming commercial transparent grade base thermoplastics into anti-biofouling resins through extrusion or any similar hot melt mixing processes. The re-compound solids enable a number of product reforming processes, including but not limited to thermoforming, profile extrusion, injection molding, blow molding, blow filming, film casting, and spinning into articles of different shapes and geometries or overmolding on plastic substrates that can resist surface adsorption of microbes, mammalian cells, proteins, peptides, nucleic acids, steroids and other cellular constituents after solidification. The articles formed thereof additionally exhibit mechanical reinforcement and no leaching while retain the optical clarity of the base thermoplastics in the same product form as quantified in terms of the light transmittance and haze.

CROSS REFERENCE TO RELATED APPLICATION

This is a divisional patent application of U.S. non-provisional patentapplication Ser. No. 15/415,426, filed on Jan. 25, 2017, the disclosureof which is herein incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to methods for modifying transparent gradebase thermoplastics to increase their surface biofouling resistance withadded mechanical reinforcement while retain the light transmittance andhaze of the base thermoplastics after product forming processes. Inparticular, the present invention relates to methods of introducingsuitable chemical modifiers to the base materials through extrusion orhot melt mixing in order to increase surface biofouling resistance ofthe base thermoplastics. It also relates to the product formedtherefrom.

BACKGROUND OF THE INVENTION

Transparent plastics ordinarily are rigid thermoplastics such aspoly(methyl methacrylate) (PMMA), polystyrene (PS), polyethyleneterephthalate (PET), polycarbonate (PC), polymethylpentene (PMP),polysulfone, polyamide (PA), polyvinyl chloride (PVC), styreneacrylonitrile (SAN), styrene-methacrylate based copolymer, polypropylenebased copolymer, acrylonitrile butadiene styrene (ABS), polyimide (PI)and cellulosic resins. Transparent plastics are regarded as plasticswith light transmission percentage of more than 80%. These plastics canbe used in aquariums, signboards, automobile taillights, bathtub liners,sinks, cell phone display screens, backlight optical waveguides forliquid crystal displays (LCD), lighting bulb shells and aircraft windowpanels due to their low cost and ease of processing as well as theirlightweight, shatter resistant, low-temperature impact resistant andchemical resistant properties. They are therefore expected to replacethe unbendable oxide glasses in a wider range of applications in thenear future apart from the large application base in commodity productsincluding food and cosmetics packaging, construction, electricalappliances, toys, stationery, spectacles and more.

There is a strong motivation for incorporation of surface biofoulingresistance into optically clear plastics that can be found in daily lifeapplications, for instance, the dust collection chamber of the vacuumcleaner, the refillable liquid soap dispenser and the paper roll holderwhich necessitates sanitary conditions against microbes. Previousresearch showed that 50% of vacuum cleaner brushes contained fecalbacteria and E. coli. Another data supported that 25% of the refillablesoap dispenser in the public restrooms was contaminated with more than 1million colony-forming units (CFU) per milliliter of bacteria and 16% ofthe soap samples contained coliform bacteria. On average, at least10,000-fold increase in the bacteria population is expected over 5 hoursin a non-sanitized and nutrient-enriched ambience.

Conventional non-fouling modification of polymers is usually achieved bysurface modification and coating with hydrophilic layers on thepolymeric surfaces after molding. This can be demonstrated in a numberof disclosures as follows.

CN102942708 discloses a wet chemical approach to obtain surfacehydrophilic polypropylene material in the form of film, mesh, wire,particles or microspheres, by grafting a monomeric maleic anhydride ontoa polypropylene and then polyethylene glycol onto the maleic anhydride.This is yet a surface modification process on a preform of polypropylenematerial to impart the antifouling properties.

One non-patent citation describes a combined self-hydrogel-generatingand self-polishing crosslinked polymer coating, where hydrolysablepolymer chains are kept leaching out from the top to keep the surfaceantifouling (Xie et al. Polymer 2011, 52, 3738).

DE19643585 reveals an anti-adhesive agent, containing sphingolipid,against microorganisms, viruses, parasites and protozoa.

US20110177237 utilizes chromen-4-one derivatives as non-toxic,environment friendly antifouling agent, a coating material for objectssubmerged under the water and subject to biofouling.

WO2016015005 discloses a three-component, protein-repellent dentalbonding system based on 2-methacryloyloxyethyl phosphorylcholine as theactive protein repellent agent.

US20090094954 discloses an antifouling composite material throughdisposing an inorganic fine particle layer on a surface of thesubstrate.

Some employ various classes and structures of functional polymers ascoatings to impart fouling resistance of relevantly compatiblesubstrates towards marine organisms as exemplified by US20160002489,US20150197644, US20100130665 and U.S. Pat. No. 6,303,078.

Especially to living matters, one even adopts the time release ofantimicrobial compounds from the polymeric materials, such asUS20150218390, to avoid adherence of microorganisms to form a biofilmand/or kill the microorganisms already adhered inhibiting their growth,which is ecologically unfriendly and potentially toxic to the mankind.

As inspired from the earlier fundamental researches, surface energy ofthe substrate definitely plays an important role. Minimal long-termadhesion of microbes is associated with surfaces having initial surfacetensions between 20 and 30 mN/m, i.e. low-energy surfaces. Silicones andfluoropolymers are the two well-known non-fouling organic compoundshaving been used as the essential coating ingredients due to their lowsurface energies.

WO2016110271 discloses a built-in modification method to enableantimicrobial property of polymers, through repelling the microbes fromthe article surfaces based on an antifouling agent. The antifoulingagent is selected from a hydrophilic forming group consisting of polyol,polyoxyether, polyamine, polycarboxylate, polyacrylate,polyvinylpyrrolidone, polysaccharide, Zwitterionic polyelectrolyte, acopolymerized system of polymer segments of mixed charges and/or aninterpenetrating blend mixture of cationic and anionic polymers. Theagent has to react with maleic anhydride on a polymer carrier as acoupling linker and to be blended with the base polymer.

US20100280174 discloses a melt blending process to incorporate non-ionicsurfactants having an HLB number of less than or equal to 10 intohydrophobic polymers. The molded articles show the protein resistancedue to surface migration of the surfactants. However, there are norelevant claims to indicate the bulk physical change and moreastoundingly, mechanical reinforcement, as well as retention of theoptical properties after the said modification.

SUMMARY OF THE INVENTION

Accordingly, in a first aspect of the present invention, a meltcompounding strategy to non-covalently blend or covalently graft thenon-fouling moieties onto the backbones of various optically clearcopolymer resins is employed into a method for modifying a transparentgrade thermoplastic, wherein said method comprises firstly usingreactive melt extrusion on a screw extruder to produce granular resinswith non-fouling property from a composition comprising said transparentgrade thermoplastic and then injection molding for product forming frompelletized granules prepared early on. The transparent gradethermoplastic being modified by the present method includes but notlimited to homopolymers, copolymers and blends of polyolefins, cyclicpolyolefins, acrylics, acetates, styrenics, polyesters, polyimides,polyaryletherketones, polycarbonates, polyurethanes and thermoplasticelastomers. In a preferred embodiment, the transparent gradethermoplastics being modified by the present method includes but notlimited to poly(methyl methacrylate) (PMMA), polystyrene (PS),polyethylene terephthalate (PET), polycarbonate (PC), polymethylpentene(PMP), polysulfone, polyamide (PA), polyvinyl chloride (PVC), styreneacrylonitrile (SAN), styrene-methacrylate based copolymer, polypropylenebased copolymer, acrylonitrile butadiene styrene (ABS), polyimide (PI)and cellulosic resins, methyl methacrylate butadiene styrene (MBS),styrene ethylene butylene styrene block thermoplastic elastomer (SEBS),etc. The method of the present invention also includes blending one ormore linear or multi-armed structures of non-ionic surfactants asnon-fouling modifiers, polyolefin elastomers and polyurethane as impactmodifiers, initiators, cross-linking agents, nucleators, anti-oxidantsand/or other auxiliary additives with the transparent grade basethermoplastics prior to or during melt processing of the basethermoplastics. When the afore-mentioned transparent grade basethermoplastics, chemical modifiers and auxiliary additives are addedinto the composition prior to said melt processing by extrusion, theyshould be blended thoroughly and then extruded to form a functionalmasterbatch. The formed masterbatch is then further blended with thetransparent grade base thermoplastics for subsequent extrusion. Saidmelt processing can be achieved on either a single-screw or twin-screwextruder operated within a proper processing temperature range accordingto different melting temperatures of the transparent grade basethermoplastics and other main components for modifying the same, e.g.from 150 to 250° C. In a preferred embodiment, the processingtemperature of said melt processing ranges from 170 to 220° C. Aftersaid melt processing, the melt processed composition is then subjectedto cooling, followed by pelletization either separately from orcontinuously into the same extruder to obtain either a solid standaloneor a masterbatch concentrate resin. The obtained solid or masterbatchconcentrate resin is then subjected to injection molding to reform intoan article with desired shape and dimension. Apart from injectionmolding, other molding methods such as profile extrusion, blow molding,blow filming, film casting, spinning and overmolding said standalone ormasterbatch concentrate resin on plastic substrates can also be appliedto reformation into an article.

The second aspect of the present invention relates to the compositionfor forming a functional polymer or a masterbatch concentrate resin.Said composition comprises said transparent grade base thermoplastics(70-99 wt %) as described in the first aspect and hereinafter, impactmodifiers (0-30 wt %), chemical or functional modifiers (0.5-10 wt %)including non-fouling modifiers (0.1-5 wt %), and other additives (0.1-2wt %) such as one or more of initiators, cross-linking agents,nucleators, anti-oxidants, and/or auxiliary additives (0.1-6 wt %). Inthe case that impact modifiers are required, the weight percentagethereof ranges from 0.1-30 wt %. Said non-fouling modifiers include oneor more of linear and/or multi-armed structures of non-ionicsurfactants. In a preferred embodiment, said non-ionic surfactantsinclude fatty alcohol polyoxyalkylene ethers, polyoxyalkylenesorbitan/sorbitol fatty acid esters, polyoxyalkylene alkyl amines,polyether glycols, fatty acid alkanolamides and their derivatives. Morespecifically, said non-ionic surfactants include polyethylene glycol(PEG) sorbitol hexaoleate, AEO-5 and polyetheramine (e.g., JEFFAMINE®D-230 or T-5000), wherein the PEG sorbitol hexaoleate has a molecularweight ranging from 2,000 to 20,000 Da; the polyetheramine has amolecular weight ranging from 200 to 6,000 Da. Said impact modifiersinclude polyolefin elastomer, chlorinated polyolefin, styrenic blockcopolymer, ethylene propylene rubber, ethylene vinyl alcohol, acrylicresin, polyurethane, ethylene copolymerized polar terpolymer, reactivemodified elastomer. Said initiators include an acid/base catalyst. Morespecifically, said initiators include tosylic acid, tetramethylammoniumhydroxide or an organic peroxide, such as dicumyl peroxide,bis(tert-butylperoxyisopropyl)benzene,2,5-bis(tert-butylperoxy)-2,5-dimethylhexane and benzoyl peroxide, whichcan exist in either standalone form or being supported on fillerparticles. Said cross-linking agents are rubber vulcanization agent.More specifically, said cross-linking agents include triallylisocyanurate, N,N′-m-phenylene dismaleimide and/or sulfur. Morespecifically, said nucleators include MILLAD® NX8000, MILLAD® 3988, ADKSTAB NA-18 and/or ADK STAB NA-25. More specifically, said anti-oxidantsinclude butylated hydroxytoluene, IRGANOX® 1010, IRGANOX® 1076, IRGANOX®1098, IRGAFOS® 168 or IRGANOX® B 225. Said other auxiliary additivesinclude alumina nanoparticles, light stabilizers, antiblocks,reinforcing fillers, optical brighteners, colorants, flame retardantsand deodorants. More specifically, said auxiliary additives are aluminananoparticles (AEROXIDE® Alu C). By the present method and composition,deviation of optical transmittance and haze of the transparent gradebase thermoplastics is less than 20% at 1 mm thickness under thestandard of ASTM D1003, meaning that the transparency of the basethermoplastics is well maintained while they also comply with variousstandards for different applications including those plastics which aresafe for food and drinks because the modifiers and other main componentsadded into the composition for modifying the transparent grade basethermoplastics according to the present invention enable biofoulingresistance and mechanical reinforcement of the end product or moldedarticle reformed therefrom against fluid biological matters, such asmicrobes, mammalian cells, proteins, peptides, nucleic acids, steroidsand other cellular constituents.

These and other examples and features of the present invention andmethods will be set forth in part in the following Detailed Description.This Summary is intended to provide an overview of the presentinvention, and is not intended to provide an exclusive or exhaustiveexplanation. The Detailed Description below is included to providefurther information about the present disclosures and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing an incubation protocol formicrobial adsorption tests on different molded circular plate samplesreformed by injection molding from the melt processed compositioncomprising the modified transparent grade base thermoplastics accordingto certain embodiments of the present invention.

FIG. 2 is an illustration of the main components in the composition formodifying the transparent grade base thermoplastics according to certainembodiment of the present invention.

FIG. 3 is a schematic diagram showing a workflow of both one-step andtwo-step methods for modifying the transparent grade base thermoplasticsaccording to certain embodiments of the present invention.

FIG. 4 illustrates the test results of the molded plate samples made ofone of the modified transparent grade base thermoplastics (MBS-M)against a control (MBS): (A) is an image of molded MBS vs MBS-M platesamples placed on top of a piece of paper; (B) shows microbialadsorption test of the molded MBS vs MBS-M circular plate samples by animage taken from aerial view. The left three sets of image representsthe microbial adsorption of MBS towards Escherichia coli, and the rightthree sets of image represents the microbial adsorption of MBS towardsStaphylococcus Aureus.

FIG. 5 illustrates the test results of the molded plate samples made ofone of the modified transparent grade base thermoplastics (PPM-M)against a control (PPM): (A) is an image of molded PPM vs PPM-M platesamples placed on top of a piece of paper; (B) is an image of molded PPMvs PPM-M plate samples after being tested in a protein repellent assayaccording to the protocol as described hereinafter; (C) shows microbialadsorption test of the molded PPM vs PPM-M circular plate samples by animage taken from aerial view. The left three sets of image representsthe microbial adsorption of PPM towards Escherichia Coli, and the rightthree sets of image represents the microbial adsorption of PPM towardsStaphylococcus Aureus.

DETAILED DESCRIPTION OF THE INVENTION

References in the specification to “one embodiment”, “an embodiment”,“an example embodiment”, etc., indicate that the embodiment describedcan include a particular feature, structure, or characteristic, butevery embodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to affect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed.

Values expressed in a range format should be interpreted in a flexiblemanner to include not only the numerical values explicitly recited asthe limits of the range, but also to include all the individualnumerical values or sub-ranges encompassed within that range as if eachnumerical value and sub-range is explicitly recited. For example, aconcentration range of “about 0.1% to about 5%” should be interpreted toinclude not only the explicitly recited concentration of about 0.1 wt. %to about 5 wt. %, but also the individual concentrations (e.g., 1%, 2%,3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, and3.3% to 4.4%) within the indicated range.

As described herein, the terms “a” or “an” are used to include one ormore than one and the term “or” is used to refer to a nonexclusive “or”unless otherwise indicated. In addition, it is to be understood that thephraseology or terminology employed herein, and not otherwise defined,is for the purpose of description only and not of limitation.Furthermore, all publications, patents, and patent documents referred toin this document are incorporated by reference herein in their entirety,as though individually incorporated by reference. In the event ofinconsistent usages between this document and those documents soincorporated by reference, the usage in the incorporated referenceshould be considered supplementary to that of this document; forirreconcilable inconsistencies, the usage in this document controls.

In the methods of manufacturing described herein, the steps can becarried out in any order without departing from the principles of theinvention, except when a temporal or operational sequence is explicitlyrecited. Recitation in a claim to the effect that first a step isperformed, and then several other steps are subsequently performed,shall be taken to mean that the first step is performed before any ofthe other steps, but the other steps can be performed in any suitablesequence, unless a sequence is further recited within the other steps.For example, claim elements that recite “Step A, Step B, Step C, Step D,and Step E” shall be construed to mean step A is carried out first, stepE is carried out last, and steps B, C, and D can be carried out in anysequence between steps A and E, and that the sequence still falls withinthe literal scope of the claimed process. A given step or sub-set ofsteps can also be repeated.

Furthermore, specified steps can be carried out concurrently unlessexplicit claim language recites that they be carried out separately. Forexample, a claimed step of doing X and a claimed step of doing Y can beconducted simultaneously within a single operation, and the resultingprocess will fall within the literal scope of the claimed process.

Definitions

The singular forms “a,” “an” and “the” can include plural referentsunless the context clearly dictates otherwise.

The term “about” can allow for a degree of variability in a value orrange, for example, within 10%, or within 5% of a stated value or of astated limit of a range.

The term “independently selected from” refers to referenced groups beingthe same, different, or a mixture thereof, unless the context clearlyindicates otherwise. Thus, under this definition, the phrase “X1, X2,and X3 are independently selected from noble gases” would include thescenario where, for example, X1, X2, and X3 are all the same, where X1,X2, and X3 are all different, where X1 and X2 are the same but X3 isdifferent, and other analogous permutations.

DETAILED DESCRIPTIONS OF PREFERRED EMBODIMENTS

The present invention is not to be limited in scope by any of thefollowing descriptions. The following examples or embodiments arepresented for exemplification only.

The modification of the transparent grade base thermoplastics accordingto the present invention can be processed in either one-step or two-stepmethod (FIG. 3). The transparent grade base polymer is blended orreacted with chemical modifiers and/or auxiliary additives either beforeor during extrusion to create functional polymer (one-step) ormasterbatch (two-step). Representative examples of transparent gradebase thermoplastics include (-impact modified) polypropylene random(PPR) copolymers and homopolymer (PPH) and several thermoplasticelastomers, such as methyl methacrylate butadiene styrene (MBS), styreneethylene butylene styrene block thermoplastic elastomer (SEB S) andpolyurethane. Melt processing can be achieved on either single-screw ortwin-screw extruder operated with a proper processing temperaturewindow. The extruder can be equipped with a cooling water bath and apelletizer to obtain solid standalone or a masterbatch concentrate resinprior to article reforming by injection molding, for example. Theprocessing temperature ranges from 170 to 220° C. for said transparentgrade base thermoplastics and other main components for modifying thesame.

One or more of linear and/or multi-armed structures of non-ionicsurfactants is/are selected as the non-fouling modifiers. The non-ionicsurfactants are chosen from fatty alcohol polyoxyalkylene ethers,polyoxyalkylene sorbitan/sorbitol fatty acid esters, polyoxyalkylenealkyl amines, polyether glycols, fatty acid alkanolamides and theirderivatives. Polyethylene glycol (PEG) sorbitol hexaoleate, AEO-5 andpolyetheramine (JEFFAMINE® D-230 or T-5000) are preferred non-foulingmodifiers. Proper ratio and combination of functional modifiers is keyto the anti-biofouling performance and retention of transparency of thetransparent grade base thermoplastic materials. Typical ratio isadjusted from 0.5 to 10% on a weight basis with respect to the totalweight of the composition. In a specific embodiment, thePEG sorbitolhexaoleate has a molecular weight ranging from 2,000 to 20,000 Da (or 2to 20 kDa). In another specific embodiment, said polyetheramine has amolecular weight ranging from 200 to 6,000 Da.

Elastomers, such as polyolefin elastomer (POE) and thermoplasticpolyurethane (TPU), are chosen as impact modifiers for modifyingdifferent transparent grade base thermoplastics. VISTAMAXX™ and ENGAGE™series POE and ELASTOLLAN® series TPU are preferably suggested in thiscase. The suggested ratio ranges from 0.1 to 30% by weight with respectto the total weight of the composition in order to augment the impactstrength. Initiators and additives including tosylic acid,tetramethylammonium hydroxide, and/or an organic peroxide, such asdicumyl peroxide, bis(tert-butylperoxyisopropyl)benzene,2,5-bis(tert-butylperoxy)-2,5-dimethylhexane and benzoyl peroxide, in aweight percentage from 0.01% to 0.2% with respect to the total weight ofthe composition are added to initiate covalent grafting of thenon-fouling modifiers onto the base polymers and/or impact modifiers.

Other additives, such as anti-oxidant, cross-linking agent, opticalbrightener, color masterbatch, odor absorbent, etc. are chosen tocontrol the appearance and the scent of the articles. The anti-oxidantis preferred to be selected from butylated hydroxytoluene, IRGANOX®1010, IRGANOX® 1076, IRGANOX® 1098, IRGAFOS® 168 or IRGANOX® B 225 witha weight percentage to the total weight of the composition from 0.1 to 2wt %. The cross-linking agent is preferred to be selected from triallylisocyanurate, N,N′-m-phenylene dismaleimide or sulfur with a weightpercentage to the total weight of the composition from 0 to 1 wt %. Theinitiator is preferred to be selected from dicumyl peroxide,bis(tert-butylperoxyisopropyl)benzene or benzoyl peroxide with a weightpercentage to the total weight of the composition from 0.01 to 0.2 wt %.The nucleator is preferred to be selected from MILLAD® NX8000, MILLAD®3988, ADK STAB NA-18 or ADK STAB NA-25 with a weight percentage to thetotal weight of the composition from 0 to 3 wt %. An auxiliary additiveis preferred to be alumina nanoparticles (AEROXIDE® Alu C) forenhancement of the heat deflection temperature of base polymers withsuggested weight percentage to the total weight of the composition from0.1 to 4 wt %.

During injection molding, the cycle time typically ranges from a fewseconds to 5 minutes for extremely thick-wall parts per shot. Onaverage, the injection falls in the range between 20 and 60 seconds fora well-designed mold and with a proper barrel and mold temperaturecontrol. For instance, samples of dogbone tensile test bars (Type I,ASTM D638), Izod impact test bars (ASTM D256), flat circular plates withthickness of 1.5 mm and diameter of 60 mm for optical haze/transmittance(ASTM D1003) and yellowness index (ASTM E313) measurement andrectangular strips for heat deflection temperature measurement (ISO 75)were produced on a 150-ton injection molding machine in one single shotfrom the mold cavity. Extrusive compounding was performed on aco-rotating twin-screw extruder. The extruder had a screw diameter of 26mm, a screw length-to-diameter (L/D) ratio of 42:1 and an adjustablespeed of 50-500 rpm. Its barrel was divided into 7 temperature zones,one of which was located at the die orifice. The extruder was equippedwith a volumetric feeder composed of two separate compartments that canfeed two different types of raw materials at an equivalent ratio.

Protein repellent assay procedures are herein described as follows:

(a) 0.5 ml bovine serum albumin (BSA)/0.01 M phosphate-buffered saline(0.1 g/ml, pH 7.4) protein solution is wetted on a flat surface of amolded circular plate sample;(b) The protein solution is placed at room temperature for half an hourfor adsorption;(c) The protein solution is withdrawn by aspiration;(d) Bradford reagent (Cat. no. B6916, Sigma) of the same volume isdeposited on the affected area to stain the potentially protein-fouledsample surface;(e) Color change of the Bradford reagent (from brown to blue)qualitatively indicates the presence of adsorbed proteins.

The incubation protocol for microbial adsorption tests on the moldedcircular plate samples is herein described by the schematic diagram inFIG. 1. The starting inoculum concentration of E. coli (ATCC® 8739™) andS. aureus (ATCC® 6538P™) was about 0.9×10⁶ and 8×10⁸ cells/ml in 1/500NB solution (1/500 NB refers to the 500× diluted Nutrient Broth with pHadjusted to 6.8-7.2) for challenging the sample surface. Result of theadsorption tests are illustrated in the following examples, and also inFIG. 4B and FIG. 5C.

EXAMPLES

The embodiments of the present invention can be better understood byreference to the following examples which are offered by way ofillustration. The present invention is not limited to the examples givenherein.

Example 1

The modification of MBS, a highly transparent methyl methacrylatebutadiene styrene plastic compound, was rendered by extrusivecompounding of 94% MBS resin with 1% IRGANOX® B 225 and 5% AEO-5, afatty alcohol ethoxylate, on a weight basis with a processingtemperature ranging from 180° C. to 210° C. to obtain functional resindirectly. The modified formulation was re-pelletized as standalone resin(herein annotated as MBS-M) that could be fed into an injection moldingmachine (with processing temperature of 210° C.) to obtain plasticsamples dictated by the mold tooling design. FIG. 4A shows that themolded plate samples made of MBS-M according to the present methodremain essentially transparent. The characterization results aresummarized in Table 1. The impact strength of MB S-M was almost doublethat of the base MBS plastic apart from the added microbial repellentperformance towards E. coli, a Gram-negative and S. aureus, aGram-positive bacteria. MBS-M passed ISO 22196's antibacterialrequirement by showing a nearly log-4 reduction of bacterial countsafter intimate contact with corresponding molded plate samples withaccredited report certificate. The plate samples also indicatedzero-growth ratings consistently over 21 days under ASTM G21 and ASTMG22 standards with accredited report certificates. Besides, the totalaerobic microbial count and the total combined molds and yeasts of theMBS-M pellets were less than 10 CFU/g according to USP <61> enumerationtests with accredited report certificate.

TABLE 1 Izod % reduction % reduction Impact Elongation Mechanical of E.coli of S. aureus Transparency Haze Strength HDT at break Strengthadsorption adsorption Sample (%) (%) (KJ/m²) (° C.) (%) (N/mm²) (%) (%)MBS 88.4 7.3 24.42 83.5 89.2 28.04 — — (Control) MBS-M 89.6 6.5 47.1179.8 82.6 24.37 99% 96%

Example 2

The modification of PPR, a transparent polypropylene random copolymer,was rendered by extrusive compounding of PPR resin with 30% polyolefinelastomer (VISTAMAXX™ 6202, ExxonMobil), 2% JEFFAMINE® D-230, 2%poly(ethylene glycol) sorbitol hexaoleate, 3.75% alumina nanoparticles,0.1% dicumyl peroxide, 0.05% triallyl isocyanurate and 0.01% CBS-127, anoptical brightener, on a weight basis with processing temperatureranging from 170° C. to 190° C. to obtain a functional masterbatchconcentrate (herein, annotated as PPR-M) after pelletization. Themasterbatch was dry blended at a ratio of 1:1.5 w:w PPR with 0.1%overall by weight of NX8000 and subsequently fed into an injectionmolding machine (with processing temperature of 190° C.) to obtainplastic samples. The characterization results are summarized in Table 2.Alumina nanoparticles helped to minimize the reduction of heatdeflection temperature (HDT) by counteracting the influence of additionof polyolefin elastomer.

TABLE 2 Izod % reduction of % reduction Impact E. coli of S. aureusTransparency Haze Strength HDT Yellowness Protein adsorption adsorptionSample (%) (%) (KJ/m²) (° C.) Index repellency (%) (%) PPR 84.1 26.47.21 78.1 10.6 No — — (Control) PPR-M 82.5 28.2 15.42 77.6 11.9 Yes >99%>99%

Example 3

The modification of PPM, an impact-modified polypropylene compound, wasrendered by extrusive compounding of PPM resin with 2% JEFFAMINE® D-230,2% AEO-5, 1% MILLAD® NX8000, 0.1% dicumyl peroxide and 0.05% triallylisocyanurate with processing temperature ranging from 170° C. to 190° C.to obtain a functional masterbatch concentrate (herein, annotated asPPM-M) after pelletization. The masterbatch was dry blended at a ratioof 1:1.5 w:w PPM with 0.1% overall by weight of IRGANOX® 1010 and 0.1%overall by weight of IRGAFOS® 168 for injection molding with processingtemperature of 190° C. FIG. 5A shows that the molded plate sample ofPPM-M is essentially transparent; The characterization results aresummarized in Table 3, and also in FIG. 5B and FIG. 5C. FIG. 5B showsthat when BSA protein solution added on the molded plate sample made ofPPM-M effectively repelled protein adsorption onto the surface. Solutionof bovine serum albumin (BSA), a protein molecule, was dropped on thesample surface for five minutes prior to aspiration. The BradfordReagent (Coomassie Blue), which could react with the nitrogen of theBSA, was then dropped on the sample surface. The sample surface whereBSA was adsorbed on would change Bradford Reagent from brown into bluecolor, indicating the adsorption of protein on the surface. Thosesurfaces repelled protein adsorption would keep Bradford reagent brown,indicating the protein repellency of sample surface. FIG. 5C shows thatE. coli and S. aureus are substantially repelled (>99%) by the moldedplate sample made of PPM-M. PPM-M passed ISO 22196 by showing a nearlylog-4 reduction of bacterial counts after intimate contact withcorresponding molded plate samples with accredited report certificate.PPM-M also passed ASTM G21 and ASTM G22 by indicating zero-growthratings consistently over 21 days with accredited report certificate.Besides, PPM-M showed zero rating meaning a complete resistance againstthe pink staining by Streptoverticillium reticulum with accreditedreport certificate. Under ASTM E2149, a dynamic shake flaskantibacterial test, PPM-M molded plates showed 100% and 90.7% reductionof E. coli and S. aureus respectively upon 24 hours of incubation withaccredited report certificate. Under ISO 20645, an agar diffusion platetest, nil growth of E. coli, S. aureus, Salmonella typhimurium,Campylobacter jejuni under samples were observed while zero zone ofinhibition were obtained with accredited test certificate, thusimplicative of no free biocide leaching. The samples were antibacterialtowards Klebsiella pneumoniae by showing 72% reduction of counts after24 hours of contact even with agar slurries under ASTM E2180 withaccredited report certificate. Furthermore, the total aerobic microbialcount and the total combined molds and yeasts of the PPM-M pellets wereless than 10 CFU/g according to USP <61> enumeration tests withaccredited report certificate. The samples also complied with theoverall migration limits for the three types of stimulants used (3% w/vacetic acid, 10% v/v ethanolic solution and rectified olive oil) at 70°C. for 2 hours as well as the two types of stimulants (3% w/v aceticacid, 10% v/v ethanolic solution) at 100° C. for 4 hours, as set out byEU No. 10/2011 as well as conformed to US FDA 21 CFR 177.1520(d), Items3.1a and 3.2a as a polypropylene copolymer for intended uses in foodcontact articles. Relevant certificates issued from accredited agencywere available. Furthermore, the total aerobic microbial count and thetotal combined molds and yeasts of the PPM-M pellets were less than 10CFU/g according to USP <61> enumeration tests with accredited reportcertificate. The samples were also proven to be biocompatible under ISO10993-4 (both direct contact and extract method) hemolysis tests and ISO10993-5 (MEM elution method) cytotoxicity tests with accredited reportcertificates. Last but not least, an even slight increase of the impactstrength of the base PPM plastic after modification was resulted.

TABLE 3 Izod % reduction of Impact Repellency E. coli % reduction ofTransparency Haze Strength HDT towards adsorption S. aureus adsorptionSample (%) (%) (KJ/m²) (° C.) Protein (%) (%) PPM 81.9 23.7 44.55 71.8No NA NA (Control) PPM-M 82.6 20.3 47.46 73.1 Yes >99% >99%

Example 4

The modification of PPH, a transparent polypropylene homopolymer, wasrendered by extrusive compounding of PPH resins with 30% VISTAMAXX′3980FL, 2% JEFFAMINE® D-230, 2% poly(ethylene glycol) sorbitolhexaoleate, 0.1% dicumyl peroxide, 0.05% triallyl isocyanurate and 3.75%alumina nanoparticles with processing temperature ranging from 180° C.to 200° C. The reformulated pellets were then directly subjected toinjection molding (with processing temperature of 200° C.) to get moldedsamples. The characterization results are summarized in the table below.The impact strength increased significantly by more than 120% withrespect to the base PPH plastic. Alumina nanoparticles were added tokeep the heat deflection temperature (HDT) of PPH as high as about 80°C. for warm water contacting applications. Characterization results aresummarized in Table 4.

TABLE 4 % Izod % reduction reduction Impact Repellency of E. coli of S.aureus Yellowness Transparency Haze Strength HDT towards adsorptionadsorption Sample Index (%) (%) (KJ/m²) (° C.) Protein (%) (%) PPH 10.0683.9 17.0 4.49 98.9 No NA NA (Control) PPH-M 15.83 81.6 29.5 9.94 79.2Yes >99% >99%

Example 5

The modification of SEBS, a styrene ethylene butylene styrene blockthermoplastic elastomer, was rendered by extrusive compounding of SEBSresins with 0.1% tosylic acid, 2.5% polyethylene glycol (averagemolecular weight of 10,000) and 2.5% AEO-5 on a weight basis withprocessing temperature ranging from 170° C. to 220° C. The reformulatedpellets were directly subjected to injection molding (with a processingtemperature of 210° C.) to obtain molded samples. Characterizationresults are summarized in Table 5

TABLE 5 % reduction % reduction Repellency of E. coli of S. aureusYellowness Transparency Elongation at towards adsorption adsorptionSample Index (%) Haze (%) break (%) Protein (%) (%) SEBS 8.12 82.5 20.2420% No NA NA (Control) SEBS-M 10.03 79.2 26.4 400% Yes >99% >98%

What is claimed is:
 1. A composition for forming a functional polymer or a masterbatch concentrate resin comprising a transparent grade base thermoplastics at 70-99 wt %, impact modifiers at 0.1-30 wt %, chemical modifiers at 0.5-10 wt %, and other additives at 0.1-6 wt %, wherein said chemical modifiers comprise non-fouling modifiers in 0.1-5 wt %; and wherein said other additives comprise one or more of initiators, cross-linking agents, nucleators, anti-oxidants, and/or auxiliary additives in 0.1-6 wt %.
 2. The composition of claim 1, wherein said transparent grade base thermoplastics comprise homopolymers, copolymers and blends of polyolefins, cyclic polyolefins, acrylics, acetates, styrenics, polyesters, polyimides, polyaryletherketones, polycarbonates, polyurethanes and thermoplastic elastomers.
 3. The composition of claim 1, wherein said transparent grade base thermoplastics comprises poly(methyl methacrylate) (PMMA), polystyrene (PS), polyethylene terephthalate (PET), polycarbonate (PC), polymethylpentene (PMP), polysulfone, polyamide (PA), polyvinyl chloride (PVC), styrene acrylonitrile (SAN), styrene-methacrylate based copolymer, polypropylene based copolymer, acrylonitrile butadiene styrene (ABS), polyimide (PI) cellulosic resins, methyl methacrylate butadiene styrene (MBS), and styrene ethylene butylene styrene block thermoplastic elastomer (SEBS).
 4. The composition of claim 3, wherein said polypropylene based copolymer comprises polypropylene random copolymer (PPR), impact-modified polypropylene compound (PPM) and polypropylene homopolymer (PPH).
 5. The composition of claim 1, wherein said non-fouling modifiers comprise one or more of linear and/or multi-armed structures of non-ionic surfactants and are in a concentration from 0.5 wt % to 10 wt %.
 6. The composition of claim 5, wherein said non-ionic surfactants comprise fatty alcohol polyoxyalkylene ethers, polyoxyalkylene sorbitan/sorbitol fatty acid esters, polyoxyalkylene alkyl amines, polyether glycols, fatty acid alkanolamides and their derivatives.
 7. The composition of claim 5, wherein said non-ionic surfactants comprise polyethylene glycol (PEG) sorbitol hexaoleate, AEO-5 and polyetheramine.
 8. The composition of claim 7, wherein said PEG sorbitol hexaoleate has an average molecular weight from 2000 to 20,000 Da.
 9. The composition of claim 7 wherein said polyetheramine has a molecular weight from 200 to 6,000 Da.
 10. The composition of claim 1, wherein said impact modifiers comprise polyolefin elastomers (POE) and thermoplastic polyurethane (TPU).
 11. The composition of claim 1, wherein said initiators comprise an acid or base catalyst and exist in either standalone form or is supported on filler particles with a weight percentage from 0.01 to 0.2 wt %.
 12. The composition of claim 1, wherein said initiators comprise tosylic acid, tetramethylammonium hydroxide, or an organic peroxide and exist in either standalone form or is supported on filler particles with a weight percentage from 0.01 to 0.2 wt %.
 13. The composition of claim 12, wherein said organic peroxide comprises dicumyl peroxide, bis(tert-butylperoxyisopropyl)benzene, 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane, benzoyl peroxide.
 14. The composition of claim 1, wherein said cross-linking agents comprise triallyl isocyanurate, N,N′-m-phenylene dismaleimide or sulfur and are in a concentration from 0.01 to 0.2 wt %.
 15. The composition of claim 1, wherein said nucleators comprise MILLAD® NX8000, MILLAD® 3988, ADK STAB NA-18 or ADK STAB NA-25 in a concentration from 0.1 to 3 wt %.
 16. The composition of claim 1, wherein said anti-oxidants comprise butylated hydroxytoluene, IRGANOX® 1010, Irganox® 1076, Irganox® 1098, Irgafos® 168 or Irganox® B 225, and are in a concentration from 0.1 to 2 wt %.
 17. The composition of claim 1, wherein said auxiliary additives comprise alumina nanoparticles and are in a concentration from 0.1 to 4 wt %.
 18. The composition of claim 7, wherein said polyetheramine comprise JEFFAMINE® D-230 or T-5000.
 19. The composition of claim 17, wherein said alumina nanoparticles are AEROXIDE® Alu C. 